Ion controller



April 29, 1952 w w K 2,594,777

ION CONTROLLER Filed July 14, 1950 f lE l 4 F L I L iVa IE E I N V [IN TOR. M70807 W M'cks Patented Apr. 29, 1952 ION CONTROLLER William Wesley Hicks, San Francisco, Calif., as-

, San Francisco, Calif., a

signor to Ionics, Inc. corporation of Califo rnia Application July 14, 1950, Serial No. 173,813

4 Claims.

This invention relates to a device for selectively discharging positive or negative ions into atmospheric air within an enclosed area such as a dwelling or a room. Particularly this invention relates to the utilization of a simple ion emitter consisting of an element such as polonium which emits alpha particles which, in turn, create both positive and negative ions, together with means which in turn create positive and negative ions at about the region of the screen or perforated plate [3. In effect, therefore, it may be said that the positive and negative ions are produced in a zone at or adjacent to the screen l3. The

maximum distance of travel of alpha particles is for selectively filtering out positive or negative ions from the ions thus. produced and circulating those ions not so filtered throughout a chamber or room.

It is well known that the presence of ions in a given space results not onlyfrom natural ionization processes but also from the production of ions by the action of electric fields, thermionic emission, radioactivity, or in other ways.

It is an object of this invention, to provide an ion controller which utilizes asource of ions other than a device which utilizes thermionic emission.

It is a further object, of this invention to provide a means for effectively controlling the introduction into a room or closed area of, ions of a given sign from a radioactive source.

Other objects and advantages of the present invention will appear from. the following specification taken in conjunction with the accompanying drawing in which;

Figure 1 illustrates, partially in. cross section, a device incorporating my invention; and

Figure 2 illustrates a circuit diagram of. the device illustrated in Figure 1.

As shown in the drawings, I provide a base H] which is adapted to support the remainder of the device which includes particularly a tubular member H which, in this. instance, forms a sleeve type electrode; an ion emitter l2 which will more fully hereinafter be'described; a grid I3 surrounding the emitter l2; a source of electric current I4; a switch IS, a rectifier l1, and a motor operated fan l8.

As illustrated in Figure. 2,,I have provided an ion emitting element which consists generally of a sheet of radioactive foil 22" formed of. polonium or one of the polonium salts. Thismaterial is covered by a protective coating 2|, in this particular instance, of gold leaf; The polonium and gold leaf are mounted upon a brass or nickel plate 23. The entire assembly, is mounted in some suitable manner upon the sleeve electrode ll. Surrounding the emitter l2 and placed generally at about 4 centimeters therefrom I provide a perforated screen grid I3 which surrounds the emitter l2 substantially as shown.

The emitting surface 2| emits alpha particles approximately 4 centimeters.

Suitable low voltage current such as conventional house current is provided from a suitable source l4 through a two pole switch IE to a rectifier I7. The negative side of the rectifier I1 is connected to the screen or perforated plate grid I3 whereas the positive side of the rectifier I1 is connected to the sleeve electrode ll, supplying a pulsating positive charge thereto. As a result there will be equal intervals of charge and no charge to the sleeve II and to the grid I3.

I have found that there are two forces which move ions. The first of these forces is the electric field which is defined by, in this instance, the electrodes H and I3. The second of these forces is the motion of air through the electric field thus created. If air is not circulated through this field ions will occupy only the zone defined by the field and will not drift therefrom. However, the ions will move within the field and negative ions will be drawn to the positive electrode ll whereas positive ions will. be drawn to the negatively charged grid l3.

If the sole force utilized in this instance were the effect of the electrostatic field, there would be a passage of negative ions toward and to the electrode l I and negative ions would thus be collected upon the electrode ll. Simultaneously, negatively charged electrode l3 would attract the positively charged ions and would collect them in the same manner.

However, since ions may also be moved by the passage of air through the electrostatic field I have provided a fan l8 which may be actuated by any suitable source of energy whereby a stream of air is caused to pass through the electric field between the electrodes Ii and I3. The. minimum air velocity required is the minimum velocity required to overcome theeffect of theelectric field. In other words, suificient air is required to overcome the effect of the electric field in attractingv the negative ions to the positively charged electrode II. The movement of air upwardly through the electrode II will deflect the negative ions from their path from the zone in which they are created toward the positively charged electrode ll into the area above and beyond the upper open end of the electrode ll.

As I have previously explained, positive ions are produced in the area adjacent the negatively charged screen grid l3. These positive ions will immediately be attracted to the negatively charged screen [3 where they will be collected. The effect of the draft of air upon these positive ions will be slight.

I prefer that the rectifier ll be of the type known as a half-wave rectifier whereby a pulsing negative charge is applied to the electrode l3 and a pulsing positive charge is applied to the electrode H. Assuming that the rectifier I1 is of the type supplying pulsing charges to the electrodes H and I3, operation of the device may briefly be described as follows: Thedouble pole switch 16 is actuated to supply current to the rectifier l1 and to the motor driving the fan l8. Negative pulsing charge is supplied to the electrode l3 and a pulsing positive charge is supplied to the sleeve electrode ll. Alpha particles will be emitted by the surface 22 and in turn will create positive and negative ions in substantial quantities at or about the region of the screen electrode 13. The positively charged sleeve electrode H, together with the screen electrode l3 will form an electric field which will cause negative ions to be attracted to the sleeve electrode and positive ions to be attracted to and collected by screen electrode IS. The passage of air through the electrode II will cause the negative ions normally seeking the electrode I I to be urged from their path toward that electrode upwardly and outwardly through the open end thereof. In this manner negative ions will be discharged into the atmosphere.

The pulsing charge upon the screen grid 13 will serve to alternately attract the positive ions thereto and to have no effect upon them. Simultaneously it will serve to repel the negative ions or to have no eiiect upon them. The pulsing charge upon the electrode II will alternately serve to attract negative ions or to have no effect upon them and simultaneously to repel the positive ions or have no effect.

The draft of air created by the fan 18 will cause the ions of both signs created in a zone at or adjacent the screen l3 to pass through the screen l3 into the area between the screen l3 and the electrode II. The pulsing charges applied to the grids H and I3 will cause the negative ions to be repelled by the electrode l3 and attracted by the electrode H, and will cause the positive ions to be repelled by the electrode H and attracted by the electrode 13. However, since the ions are produced at or adjacent the electrode 13, the effect of the pulsing negative charge will be greater upon the positive ions than will be the eiiect of the pulsing positive charge of the electrode l 1 upon the negative ions. Hence a substantially greater proportion of the positive ions will be collected upon the negatively charged screen l3. The path of the ions thus being attracted and repelled will be diverted by the draft of air being passed through the electric field with the result that a preponderance of negative ions will be discharged from the upper end of the device.

I claim:

1. In a device for controlling the ion concentration in a room in atmospheric air at atmospheric pressure, means comprising a source of alpha particle radiation arranged to radiate said particles into surrounding air, a grid adjacent said means and positioned a distance from the radiating surface of said means substantially equal to the maximum distance of travel of said alpha particles, means imposing a negative charge on said grid, and means for passing a stream of air past said grid and alpha particle source, whereby said grid will attract and trap positive ions produced by said alpha particles substan tially at the point of their production and Whereby said stream of air will sweep negative ions away from said grid into the surrounding air.

, 2. Ina device; for controlling the ion concentration in a room in atmospheric air at atmospheric pressure, means comprising a source of alpha particle radiation arranged to radiate said particles into surrounding air, a grid adjacent said means, and positioned a distance from the radiating surface of said means substantially equal to the maximum distance of travel of said alpha particles, means imposing a negative charge on said grid, and means for passing a stream of air past said grid and alpha particle source, and a positively charged sleeve electrode surrounding said source and grid and through which said stream of air passes, whereby said grid will attract and trap positive ions produced by said alpha particles substantially at the point of their production and whereby said stream of air will sweep negative ions away from said grid into the surrounding air.

3. In a device for controlling the ion concentration in a room in atmospheric air at atmospheric pressure, means comprising a source of alpha particle radiation arranged to radiate said particles into surrounding air, a grid adjacent said means and positioned a distance from the radiating surface of said means substantially equal to the maximum distance of travel of said alpha particles, means imposing an intermittent negative charge on said grid, and

means for passing a stream of air past said grid and alpha particle source, whereby said grid will attract and trap positive ions produced by said alpha particles substantially at the point of their production and whereby said stream of air will sweep negative ions away from said grid into the surrounding air.

4. A device as defined in claim 1 wherein said source of alpha particles comprises a body of radioactive polonium.

WILLIAM WESLEY HICKS.

REFERENCES CITED The following references are of record in the OTHER REFERENCES Ser. No. 376,930, 'Peycelon et al. (A. P. 0.), published May 25, 1943. 

